Synthesis, Preparation and Catalytic Activities of V-Doped TiO₂ Gel Coating on Porous α-Al₂O₃ Beads

Abstract:

TiO2 and V-doped TiO2 gel were synthesized and coated onto porous α-Al2O3 beads to study the thermal catalytic activities of oxidation reactions. Titanium isopropoxide (Ti(OPr)4) and 1,2-butadiol(Bu(OH)2) were used as starting chemicals for preparation of TiO2 gel without Vdoping. After aging at ambient temperature for one week, a TiO2 gel was obtained. The concentration of Ti(OPr)4 was varied, 0.2, 0.3, 0.7 and 2.4 M was used. For V-doping of the TiO2 gel, 0.05, 0.20 and 0.75 mole% of V was prepared by ultrasonically dissolving vanadium acetylacetone (V(acac)2) in 1,2-butadiol. The solutions were then added to Ti(OPr)4. Finally, the mixed solutions were kept under ambient temperature for one week to form the V-doped TiO2 gel. TiO2 and V-doped TiO2 were calcined at 300, 400, 500, 600, 700, and 800 °C. XRD analysis, SEM and TEM in conjunction with EDS analysis were used to identify the phases present, grain size and morphology. The TiO2 grains have a particle size in the nano-scale range. Doping TiO2 with V could retard growth of the TiO2 particles and affect phase transformation at higher calcination temperatures. Both the TiO2 and V-doped TiO2 gels were prepared and coated onto α-Al2O3 beads to test oxidation reactions in a purpose-designed reactor. The results of the catalytic reactions indicated that V-doped TiO2 had a higher oxidation activity than the undoped TiO2 gel. The content of vanadium was related to the reaction efficiency.

• Periodical: Materials Science Forum (Volumes 544-545)
• Pages: 147-150
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.544-545.147
• Online since: May 2007
• Authors: Angkhana Jaroenworaluck, Thammarat Panyathanmaporn, B. Soontornworajit, Sitthisuntorn Supothina, Sittinun Tawkaew, Siriya Jiamsakul, Tawan Sooknoi
• Keywords: Catalytic Activities, Coating, Porous α-Al₂O₃ Beads, TiO₂ Gel , V-Doped TiO₂ Gel

References

[1] M. Kaneko, I. Okura : Photocatalysis, Science and Technology (Kadansha Ltd., Japan 2002).

[2] J. Rasko, T. Kecskes, J. Kiss: Journal of Catalysis Vol. 226 (2004), p.183.

[3] H.E. Chao, Y. U. Yun, H. U. Xingfang, A. Larbor: Journal of the European Ceramic Society Vol. 23 (2003), p.1457.

[4] Jeffrey C. -S. Wu and Chih-Hsien Chen: Journal of Photochemistry and photobiology A: Chemistry Vol. 163 (2004), p.509.

[5] J.S. Dalton, P. A. Janes, N.G. Jones, J. A. Nicholson, K. R. Hallam, G. C. Allen: Environmental Pollution Vol. 120 (2002), p.415.

[6] T. Panyathanmaporn, R. Chumnanklang, S. Supothina and A. Jaroenworaluck, in Gel casting process with biopolymer in natural oil for making ceramic sphere, in proceedings of the 6 th Pacific Rim Conference on Ceramic and Glass Technology, Maui, Hawaii, USA, 11 - 16 September (2005).

DOI: 10.1002/9781118144107.ch5

[2] [4] [6] [8] [10] [12] % Yield TiO2 gel TiO2 gel_0. 05%V TiO2 gel_0. 20%V TiO2 gel_0. 75%V Catalyst Type Oxidation Reaction Carbon dioxide Formaldehyde Conversion.

DOI: 10.24275/uami.ft848q67k

[5] [10] [15] [20] [25] [30] [35] [40] TiO2 gel TiO2 gel_0. 05%V TiO2 gel_0. 20%V TiO2 gel_0. 75%V Catalyst Type % Conversion %Conversion (b) (a).

DOI: 10.24275/uami.ft848q67k